In Halo 4 those Elites are apart of an old splinter cell of the Covenant that never turned away from the Covenant ideas. As you notice there are no Brutes among their ranks because the Covenant Civil War tore the two apart. The Elites that were your allies in Halo 3 returned to their planet.
no Gravemind was the leader of the flood and that virus. The elites in halo 3 join the UNSC marines as they fight the covenant and the flood
well, that's a hard one. halo 4 will come directly after the events of halo 3 so, i would imagine so.
Go to Halopedian.com and look up the Great Schism. It explains in full detail. If you want the short version, here it is. For thousands of years, the Prophets relied on the Elites for Protection and military strength. Then the Prophets betrayed the Elites by replacing them with the Brutes. That's why when you play Halo 3: ODST you'll never see an Elite. Because the Elites were aligned with the UNSC during that conflict. Also, the Elites and Brutes have had a long history of conflict. The next time you play Halo Reach, notice the groups that attack during campaign and firefight. You'll never see a group of Brutes and Elites together. Only groups of Elites or groups of Brutes.
The elites armour is minor
yes they are.
Halo: Reach happens before Halo 3. The Elites haven't defected from the Covenant yet.
No. In Halo 3, you can only play as Spartans and Elites.
its kind of a void question because the elites are on your team in Halo 3 so you don't really see them in vehicles.
Halo Wars is about 20 Years before Halo Combat Evolved. So the Elites are part of the Covenant.
We aren't sure yet.
There are elites because I've beat the whole game there are some elites scattered around the city.
say it was an accident